Figure 1. Behavioral paradigm.

A) Trial structure (after initial learning of object locations in block 1, see Methods). On each trial, participants navigated to the remembered location of the test object (“replace” phase) and, after a short delay with a black screen, received feedback (“feedback” phase). Top shows a map of the virtual trajectory taken by the participant on each phase of a typical trial, and bottom shows example views of the virtual environment from the participant’s perspective. The name of the test object remained on the center of the screen during the entire trial. B) Participants learned two object locations over three blocks. The landmark was moved relative to the boundary at the start of block 2, and again at the start of block 3. One object was tethered to the landmark (red dot) and one object was tethered the boundary (blue dots). C) Performance was measured in terms of distance error, which is the distance between the correct test object location (purple dot) and recalled test object location for each trial in virtual units (VU). D) The relative influence of the landmark on memory for test object locations was calculated as d_B/(d_L+d_B), where d_L is the distance of the response from the test object location previously associated with the landmark and d_B is the distance of the response from the test object location previously associated with the boundary.